Responses of the Olfactory Receptor Cells to Odours

Though it has generally been conceived that olfactory discrimination occurs in the olfactory receptor cells just as in the other kinds of receptors, there has so far been no direct evidence on it. Thus, Adriani' at first thought that odours are discriminated by the local difference in the activities of various areas of the olfactory epithelium, but not by the difference in the activity of each receptor cell. Later, he2' recorded mitral cell discharges in the olfactory bulb, and concluded that odours are discriminated in the level of the olfactory cell. However, his results were still indirect, and the responses of the receptor cell to odours have not been clarified yet.